This invention relates generally to tubing drains, and more particularly concerns a very simple drain assembly characterized by ease of removal and replacement as well as by assured operation at predetermined pressure level.
Oil well tubing drains are employed to drain pressurized fluid from within the tubing when the fluid pressure in the tubing is increased. Prior tubing drains are characterized as excessively complex in construction, which add to their original as well as maintenance cost or expense. One example of such a prior drain is that shown at page 4212 of the 1957 "Composite Catalogue of Oil Field Equipment and Services", published by World Oil.